The present invention relates to an unlocking device for a supplemental door lock, and, in particular, an unlocking device for a ball hook and U-shaped catch supplemental interior door lock such as used for a pedestrian door system.
Supplemental door locks have been used in residences, motels, hotels, and apartments, for example, for many years. A supplemental door lock typically works in conjunction with the primary door lock to permit the door to be opened partially from the inside to allow the occupant of the room, for example, to observe who is at the door, without permitting full access to the occupant""s space. There may arise the situation where, for example, a child has operated or engaged the supplemental door lock and thereby preventing the parent from re-entering without damaging the door and frame. Alternatively, a situation may arise where the owner or operator of the apartment, hotel or motel, or public service officials, such as firemen or policemen, are required to enter the space where a supplemental door lock has been engaged. This may happen, for example, where someone falls asleep and a fire occurs in his space; the authorities in such a situation are unable to enter the occupant""s space without damaging the door or door frame, because of the supplemental door lock.
Supplemental door locks including exterior unlocking means have been disclosed in the past. One such supplemental door lock incorporating means for unlocking it from outside the occupant""s space is disclosed in U.S. Pat. No. 2,966,053, issued Dec. 27, 1960, to Albert E. Mintz. The Mintz patent discloses a safety door chain which may be locked and unlocked from the outside by authorized persons and may also be used in a normal way by persons on the inside. Another such supplemental door lock is disclosed in U.S. Pat. No. 3,134,252, issued May 26, 1964, to Albert E. Mintz. This patent discloses a supplemental door lock using a chain lock wherein the chain is secured at one end to a slide mounted on the door and at the other end to a key actuated lock positioned on the door frame permitting a key to be readily inserted from either inside the door or outside the door to unlock and release the chain. Another such lock is disclosed in U.S. Pat. No. 4,229,030, issued Oct. 21, 1980, to Francisco J. Tarragona Corbella which discloses a supplemental door lock including a catch member which may be operated from the outside of the door to disengage it from the retaining member. The Corbella patent uses a key on the outside of the door to rotate an arm thereby permitting the door to be unlocked.
Another such supplemental door lock which may be opened from the outside is disclosed in U.S. Pat. No. 4,815,305, dated Mar. 28, 1989, issued to William C. Smith. The Smith locking mechanism utilizes an auxiliary lock for safety chain type latch which may be used if the person desires to be able to pen the door from the outside by opening the lock. Another such supplemental door lock is disclosed in U.S. Pat. No. 5,285,666, issued Feb. 15, 1994, to Arthur W. Bartnicki. The Bartnicki patent discloses a combined deadlock and safety chain type door lock which provides means to shorten the length of the safety chain when the occupant is out of the room, but which may be opened by him from the outside when a key releases the lock. U.S. Pat. No. 5,875,660, dated Mar. 2, 1999, issued to Michael C. Olhousen teaches a chain door lock in which one of the chain links has been replaced by a coded color plastic tamperproof seal. The chain is provided with a locked cylinder which may be opened with a key from the outside.
It is apparent from the foregoing patents that various supplemental door locks have been provided with means for opening the supplemental door lock from outsides the occupant""s space. This invention provides an exterior unlocking device for a ball hook and U-shaped catch supplemental door lock.
The present invention is provided in combination with a ball hook and U-shaped catch supplemental interior door lock for a pedestrian door system. Such a door system typically includes a door and doorway. The door, as is well known, includes an exterior front, an interior back and vertical sides between the front and back of the door. The door has an open position and a closed position relative to the doorway. The doorway includes oppositely disposed vertical side jambs. The door is hinged to one of the vertical side jambs. The side jambs carry a door stop forming an L-shaped lip to receive the vertical sides of the door when in the closed position. The L-shaped lip includes a substantially perpendicular corner and has one surface substantially parallel to the front of the door when in the closed position and another surface substantially parallel to the vertical sides of the door when in the closed position.
The ball hook and U-shaped catch door lock typically includes a pivoting U-shaped catch, which is mounted at one end to the doorway. The catch includes a catch mounting base attached to the doorway and a pivoting U-shaped member hinged to the mounting base. The U-shaped member is pivotally mounted at one end to the catch mounting base. A ball hook is mounted to the back of the door in operative relationship with the U-shaped member, as is well known.
The ball hook includes a curved arm and a ball hook integral mounting base at one end of the curved arm. The ball hook mounting base is attached to the back of the door. The ball hook also includes an integral ball-shaped tip at the other end of the curved arm. The U-shaped member has opposite leg portions extending from the trough of the U-shaped member. The opposite leg portions initially extend in substantial parallel relationship from the trough of the U-shaped member a predetermined length to have a door locking portion between the parallel opposite leg portions. The parallel opposite leg portions then abruptly diverge proximate the catch mounting base to have a door unlocking portion there between adjacent the door locking portion. The door unlocking portion is sized to permit the ball-shaped tip to pass freely through the U-shaped member. The door locking portion is sized to slidably engage the curved arm of the ball hook and to prevent the ball-shaped tip from passing through the U-shaped member. The supplemental interior door lock as described is well known and in wide spread use in residences, motels, hotels, and apartments, for example.
The present invention provides an unlocking device consisting of a single thin flat elongated resilient member for insertion exteriorly between the door and the one vertical side jamb. The resilient member at the proximal end is provided with a front of door contact portion for contacting the front of the door and a handle portion diverging from the front of door contact portion for permitting grasping of the handle portion exteriorly of the door. The resilient member in the operative position between the door and the one vertical side jamb longitudinally retroverts adjacent the front of door contact portion to form a door stop corner contact edge. The resilient member then extends longitudinally arcuately towards the side of the door and in contact therewith and then turns toward the catch mounting base to form an integral vertical side of door arched contact portion. The resilient member then extends from the arched contact portion at the distal end thereof longitudinally turning abruptly away from the catch mounting base to form an integral compression recoil arm fulcrum corner. The resilient member from the compression recoil fulcrum corner arcuately extends away from the catch mounting base affixed to the doorway to form an integral compression recoil arm of predetermined length. The compression recoil arm at the distal end thereof is provided with a first uniform linear transverse contact surface.
With the unlocking device in the operative position between the door and the one vertical side jamb, the door stop corner contact edge is pressed into engagement with the door stop as the door is exteriorly closed and the side of door arched contact portion is laterally compressed between the door the one vertical side jamb as the compression recoil arm is compressed towards the back of the door by and in contact with the U-shaped member as the door is about fully closed. Whereupon, the integral ball-shaped tip of the ball hook enters the door unlocking portion of the U-shaped member as a result of about full closure of the door. The U-shaped member instantaneously and forcefully recoils out of operative engagement with the U-shaped member.
In one embodiment, the first transverse contact surface of the compression recoil arm is in operative alignment with one opposite leg portion of the U-shaped member. In the second embodiment, the first transverse contact surface has sufficient width to contact both opposite leg portions of the U-shaped member simultaneously.
In another embodiment, the compression recoil arm has a curved arm receiving slot therein of predetermined dimensions. The curved arm receiving slot divides the integral compression recoil arm to form a pair of compression recoil arm finger members. A first of the recoil finger members is provided with a second uniform linear transverse contact surface at the distal end thereof for contacting one of the opposite leg portions of the pivoting U-shaped member and a second of the recoil finger members is provided with a third uniform linear contact surface at the distal end thereof for contacting other opposite leg portion of the pivoting U-shaped member.
Preferably, the one finger member and the other finger member of the pair of finger members each have a length about equal to the length of the door locking portion of the U-shaped member.
It is desirable that the handle portion of the resilient member have an offset grip portion of reduced width which preferably carries a hand protective layer.
Preferably, the second uniform linear transverse contact surface and the third uniform linear transverse contact surfaces each have a width greater than the width of the parallel opposite leg portions of the U-shaped member.
Preferably, the curved arm receiving slot of the compression recoil arm has sufficient length to permit about full closure of the door when the door lock is engaged. Also, desirably the curved arm receiving slot of the compression recoil arm has a tapered width to accommodate the curved arm having an increase in width from the ball hook to the mounting base
Preferably, the thin flat elongated resilient member has sufficient resiliency to permit said integral compression recoil arm in the operative position to deflect towards the back of the door to permit the ball hook to enter the door unlocking portion and to recoil out of operative engagement with the U-shaped member. Desirably, the thin flat elongated resilient member is made of rolled tempered steel of predetermined thickness.
The compression recoil arm finger members desirably extend longitudinally from the compression recoil arm fulcrum corner in an arch. Desirably, the distal end of each of the recoil arm members is retroverted in operative position back towards the catch mounting base.
The compression recoil arm fulcrum corner preferably forms a longitudinal fulcrum corner interior angle of from about 140 degrees to about 150 degrees between the side of door arched contact portion and the compression recoil arm when not in operative engagement with the door lock.
The door stop contact corner desirably forms a longitudinal door stop corner interior angle of from about 80 degrees to about 90 degrees between the front of door contact portion and the side of door arched contact portion.
Preferably, the handle portion diverges from the front of door contact portion at an angle of from about 30 degrees to about 45 degrees. Preferably the offset grip portion of the handle portion has a width less than the front of door contact portion.